The present invention relates to a lateral type transistor, and more particularly to a transistor device having a multi-collector or a multi-emitter structure.
A lateral transistor which has a plurality of collectors and one emitter is used in electric equipments such as power sources. However, depending on the use of such power source devices, the current-amplification factor of each collector is required to be varied from one to the next. For this purpose, the current-amplification factor is generally changed by varying the shape of each collector region. However, with this method, the shape of the collector region must be made greater in order to have a greater current-amplification factor. Consequently, the transistor itself must be made larger, adversely affecting the packing density of the integrated circuits.
Similar problems exist with transistors of multi-emitter structure as in the case of transistors of multi-collector structure.